In message , Capitol
writes
This is a 12K btu aircon unit which puts out 3.6Kw nominal
with a nominal efficiency of 300% into 7 x 20 x 20 ft. The floor is
uninsulated, the walls have 1" of glass fibre insulation, topped by
1/2" ply, with bubble insulated metal doors. The ceiling has 4" of
glass fibre under 1/2" plasterboard, topped by 3/4 inch plywood. Plus
all the rubbish stored in the loft in case it is useful! It takes
about 1/2 an hour to heat up to 26C with 5C outside temperature..
Also useful for perhaps 1 day per year as air conditioner!

That's impressive. How much?

I paid about £230, some years ago. I think the best going price
for a similar unit now is around double that. Many hotels and pubs are
now using these units to reduce heating costs without requiring boiler
installations and oil tanks. Secondhand units can be found for about
£100, but will require regassing. Should be less than £100 for the
service. Cars are £50-85 for the service.

OK I'll pass it on. Ta

--
Tim Lamb